Integrator note — SIRIUS 3RT2024-2KB40 coupling contactor
The Siemens 3RT2024-2KB40 is a SIRIUS coupling contactor in the S0 frame size, designed for DC switching applications with a 24 VDC coil and spring-type terminals. Rated DC-1 switching at 24 V carries 10 A; at 48 V and 60 V the rating drops to 2 A, and at 220 V to 0.3 A — so for higher-voltage DC loads the contactor is limited to signal-level currents, not power switching. The coil draws an initial inrush of 1.25 A and holds at 0.7 A; arcing time is 10 ms, and the mechanical life is rated at 10 million operations typical. Mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, with a 45 mm width that occupies a single 45 mm slot in the enclosure — plan panel fill accordingly. The mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward, giving flexibility in tight cabinets.
Termination and wiring
Spring-type terminals accept solid or stranded conductors from 1 to 10 mm², or 2x (0.5 to 2.5 mm²) for daisy-chaining. Main contacts are sized for 18 to 8 AWG — verify your wire gauge fits the terminal range before terminating.
Clearance and thermal limits
Minimum clearances to adjacent components: 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm at the side — maintain these for arc-flash containment and thermal derating. Operating temperature range is -25 to +60 °C; storage range extends from -55 to +80 °C.